The present invention relates to fasteners, and more particularly, to fasteners for wire-bound media.
Wire-bound notebooks, tablets, and the like are traditionally merchandised with a pre-attached medium, typically sheets of paper. The wire binder normally takes the form of a spiral or helix, and binds the selected medium by insertion through apertures in the edge of each sheet or specimen. The sheets are secured to the wire binder so as to make accidental separation from the binder unlikely.
The wire binding of selected media, while reducing the danger of accidental separation, suffers several disadvantages. The specimens are bound in such a way that their insertion for the purpose of editing, or of adding a different medium, is impracticable. In the usual arrangement, furthermore, specimens may not be reinserted once separated from the wire binder. Moreover, the aggregate number of sheets or specimens is limited to that chosen by the manufacturer.
One approach to this problem is illustrated by the index sheet for coil wire binders of F. S. Schade, U.S. Pat. No. 2,681,655. Schade discloses the use of an extended portion of an index sheet, containing slots for registration with the spiral wire coils. A retaining rod is inserted in the pocket formed by folding the extended portion, with the rod inside the spiral to engage the coils. The insertion and removal of specimens using this fastener can be a fairly cumbersome and time consuming process. These fasteners must also be manufactured in a different version for each different coil pitch (number of coils per inch).
An alternate approach which avoids the complexity of the above fastener involves a series of apertures on a fastener or specimen to be engaged. These apertures should be profiled to firmly engage the wire coils while permitting insertion and removal without undue effort. While this approach has never been applied to spiral binders per se, M. G. Swan discloses a detachable leaf for books bound by staples, using the same concept, in U.S. Pat. No. 818,130. Swan's apertures are L-shaped, not all facing in the same direction, and the pages are inserted and removed by bending the portion containing the contrarily-facing L slot. This technique would not be advantageously extended to a multiplicity of L slots for the numerous coils of a wire binder. A. H. Schneider, in U.S. Pat. No. 3,899,842, teaches a card supporting means for a rotary card file involving two key slots which engage two metal rings. The key slots face in a direction transverse to the direction of insertion and removal of the cards. This technique, again, cannot be used to engage a multiplicity of wire coils requiring more than two points of attachment.
Accordingly, it is a principal object of the invention to facilitate the insertion of specimens of any selected medium into the wire binder of a notebook, tablet, or the like. A related object is to permit augmentation of a wire-bound medium chosen by a manufacturer with additional specimens of the same or of a different medium.
Another related object is to achieve easy reinsertion into a wire binder of specimens which have been removed.
A further object of the invention is to employ a fastener for the above purposes which allows separation of a selected medium while preserving the utility of the fastener for subsequent reattachment. A related object is to permit editing of wire-bound media.
Yet another object of the invention is that such a fastener should not be unduly complex. Insertion and removal of specimens using the fastener should be quickly and easily accomplished, yet the fastener should firmly engage the wire coils.